Effects of Direct Artery Injection on Prostate Cancer Drug Delivery and Tumor Uptake: Imaging-Based Prediction of Treatment Effectiveness

The goal of this clinical trial is to learn whether intra-arterial (IA) administration of 68Ga-PSMA improves tumor uptake and distribution compared with standard intravenous (IV) administration in patients with localized high-risk prostate cancer. The study will also evaluate the safety of the IA procedure and investigate whether advanced PET/CT imaging features can help predict the radiation dose needed for future personalized 177Lu-PSMA radioligand therapy.

The main questions it aims to answer are:

* Does intra-arterial 68Ga-PSMA administration result in higher and more homogeneous tumor uptake than standard intravenous administration? * Can PET/CT texture analysis and dosimetric modeling predict the radiation dose required to achieve a curative effect with 177Lu-PSMA therapy? * What radiation exposure and procedure-related risks are associated with intra-arterial administration for patients and medical staff?

Researchers will compare PSMA uptake and distribution after intravenous and intra-arterial administration of 68Ga-PSMA using PET/CT imaging.

Participants will:

* Undergo a standard intravenous 68Ga-PSMA PET/CT scan. * Undergo a second 68Ga-PSMA PET/CT scan following selective intra-arterial administration through the prostatic artery. * Have imaging data analyzed using advanced texture analysis and voxel-based dosimetry methods. * Undergo radical prostatectomy according to standard clinical care, with pathological analysis of surgical specimens. * Be monitored for adverse events, radiation exposure, and procedural safety throughout the study.